Several oxazolidinone derivatives have been reported in the literature some of which are relevant are given here:
U.S. Pat. No. 5,547,950 discloses and claims compounds of formula (IIa)
or pharmaceutically acceptable salts there of wherein each n is independently 1 to 3; Y is selected from a-n as defined in the patent; U, V and W are independently (C1–C6)allyl, fluoro, chloro, bromo, hydrogen or a (C1–C6)alkyl substituted with one or more of fluoro, chloro, bromo or iodo, preferably U and V are fluoro and W is hydrogen; R is hydrogen, (C1–C12)alkyl, (C3–C12)cycloalkyl, (C1–C6)alkoxy, (C1–C6)alkyl substituted with one or more of fluoro, chloro, bromo, iodo or hydroxy and q is 0 to 4 inclusive.
WO 02/06278 describes a series of oxazolidinone derivatives useful as antimicrobial agents, of the formula (IIb)
wherein T is a five to seven membered heterocyclic ring, aryl, substituted aryl; R is a substituent on T; X is CH2, CH—S, CH—O and N; Y and Z are independently selected from hydrogen, alkyl, cycloalkyl; U and C are independently selected from alkyl, halogen; W is selected from group CH2, CO, CH2NH, CH2NHCH2, S, CH2CO etc; R1 is selected from —NH(C═O)R2, wherein R2 is hydrogen alkyl, cycloalkyl, alkoxy and the like.
U.S. publication No. 2002/0137754 describes a series of oxazolidinone derivatives useful as antimicrobial agents of the formula (IIc)
wherein A represents oxazolidinone ring and the like; W is NHC(═S)R1, or —Y-het; Y is NH, O, or S; R1 is H, NH2, NHC1-4alkyl, C1-4alkenyl, etc; R2 and R3 are independently H, F, Cl or C1-2alkyl; R4 is (a) —C(═O)—CR5R6—O—R7, (b) —C(═O)—CH2S(O)n-CH3, (c) —C(═O)—CH2—S(═O)(═NR8)CH3, (d) —C(═S)—R9, etc; R5 is H; R6 is phenyl, benzyl, etc, R7 is H, CH3 or C1-4 alkanoyl; R8 is H, C1-4 alkyl, C1-4 alkanoyl, —C(═O)NH—C1-4 alkyl or —CO2C1-4 alkyl; R9 is C1-4 alkyl, CH2OR11, S—C1-4 alkyl, OC1-4 alkyl, or NR12R13; R11 is H, phenyl, benzyl, CH3 etc; R12 and R13 are independently H or C1-3 alkyl; or R12 and R13 taken together form a 5- or 6- membered saturated heterocycle, wherein said saturated heterocycle may farther contain one or two additional hetero-atoms selected from a group consisting of O, S(O)n or NR7; n is 0, 1 or 2; and m is 0 or 1.
U.S. Pat. No. 6,342,513 and WO 00/32599 discloses compounds of the formula (IIc)
wherein G represents oxazolidinone ring and the like; R1 is H, NH2, NH alkyl, alkyl, alkoxy, etc, A is
wherein R23 and R24 represents H, halogen and the like; Q is
etc., wherein Z2 is SO2—, —O—, —(NR107)—OS—, —S—, and the like; R107 is —R108CO— etc, R108 is H, alkyl, aryl etc.